JP2021525456A - How to imprint an inclined optical lattice - Google Patents

Abstract

The embodiments described herein relate to a method of manufacturing a waveguide structure having a grid having a front angle of less than about 45 ° and a back angle of less than about 45 °. This method involves imprinting a stamp on a nanoimprint resist placed on a substrate. Nanoimprint resists are exposed to the curing process. The stamp is released from the nanoimprint resist at an release angle θ using the release method. The nanoimprint resist is exposed to an annealing process to form a waveguide structure containing a plurality of lattices having a front angle α and a back angle β of less than about 45 ° with respect to a second plane on the surface of the substrate. [Selection diagram] FIG. 4C

Description

The embodiments of the present disclosure generally relate to waveguide combiners for augmented reality, virtual reality, and mixed reality. More specifically, the embodiments described herein provide waveguide combiner manufacturing utilizing nanoimprint lithography.

Augmented reality allows users to still see the surrounding environment through the display lens of eyeglasses or other head-mounted display (HMD) devices, a virtual object created for display and appearing as part of the environment. The experience of being able to still see the image of is possible. Augmented reality can include any type of input, such as audio and tactile inputs, as well as virtual images, graphics and video that enhance or enhance the environment the user experiences. As a new technology, augmented reality has many challenges and design constraints.

One such task is to display a virtual image superimposed on the surrounding environment. Waveguide combiners are used to assist in image superposition. The generated light is input-coupled to the waveguide combiner, propagates through the waveguide combiner, is output-coupled from the waveguide combiner, and is superposed on the surrounding environment. Light is coupled inside and outside the waveguide combiner using a surface relief grid. The intensity of input-coupled and output-coupled light is controlled by a surface relief grid with side walls with tilt angles. The waveguide combiner may require a grid with an inclination angle of less than about 45 degrees to the surface of the waveguide combiner or more than about 45 degrees to the normal of the surface of the waveguide combiner. .. Manufacturing a waveguide structure for use as a waveguide combiner or master for nanoimprint lithography can be difficult.

In particular, manufacturing a waveguide structure having a lattice having an inclination angle of less than about 45 degrees with respect to the surface of the waveguide structure tilts less than about 45 degrees from the nanoimprint resist without damaging the nanoimprint resist. It can be difficult due to the difficulty of releasing an angular nanoimprint lithography stamp and the difficulty of configuring an angled etching tool to generate an ion beam at an angle of less than about 45 degrees.

Therefore, a method of using a nanoimprint lithography stamp having an inclination angle of about 45 degrees or more to form a waveguide structure having a grid having an inclination angle of less than about 45 degrees with respect to the surface of the waveguide combiner is used. It is needed in this technical field.

In one embodiment, a waveguide structure manufacturing method is provided. This method involves imprinting a stamp on a nanoimprint resist placed on the surface of a substrate. The stamp includes an inverted front angle α and an inverted back angle β of about 45 ° or more with respect to the first plane of the back surface of the stamp, and a plurality of reciprocal lattices having the first dimension. Nanoimprint resists are exposed to the curing process. The stamp is released from the nanoimprint resist at an release angle θ using the release method. The nanoimprint resist is exposed to an annealing process and has a waveguide structure containing a front angle α and a back angle β of less than about 45 ° with respect to a second plane on the surface of the substrate, and a plurality of lattices having a third dimension. To form.

In another embodiment, a waveguide structure manufacturing method is provided. This method involves imprinting a stamp on a nanoimprint resist placed on the surface of a substrate. The stamp includes an inverted front angle α and an inverted back angle β of about 45 ° or more with respect to the first plane of the back surface of the stamp, and a plurality of reciprocal lattices having the first dimension. The nanoimprint resist is exposed to the curing process so that it is in an open state. The stamp is released from the open nanoimprint resist using a release method that peels the stamp from the open nanoimprint resist at a release angle θ'with respect to the second plane and second dimension of the surface of the substrate. Therefore, a plurality of transition lattices having a transition front angle α'and a transition back angle β'are formed. ^{The nanoimprint resist is exposed to an annealing process and contains a waveguide containing a front angle α 1} and a back angle β ¹ less than about 45 ° with respect to a second plane of the surface of the substrate, and multiple grids having a third dimension. The tube structure is formed from nanoimprint resist in an annealed state.

In yet another embodiment, a waveguide structure manufacturing method is provided. This method involves imprinting a stamp on a nanoimprint resist placed on the surface of a substrate. The stamp includes an inverted front angle α and an inverted back angle β of about 45 ° or more with respect to the first plane of the back surface of the stamp, and a plurality of reciprocal lattices having the first dimension. The nanoimprint resist is exposed to the curing process so that it is in an open state. The stamp is released from the open nanoimprint resist using a release method that lifts the stamp from the open nanoimprint resist at a release angle θ'' with respect to the second plane and second dimension of the surface of the substrate. Therefore, a plurality of transition lattices having a transition front angle α'' and a transition back angle β'' are formed. ^{The nanoimprint resist is exposed to an annealing process and contains a waveguide with a front angle α 2} and a back angle β ² less than about 45 ° to a second plane on the surface of the substrate, as well as multiple grids with a third dimension. The tube structure is formed from nanoimprint resist in an annealed state.

More specific description of the present disclosure outlined above is provided by reference to embodiments, some of which are shown in the accompanying drawings, so that the above-mentioned features of the present disclosure can be understood in detail. There is. However, it should be noted that the accompanying drawings merely illustrate exemplary embodiments and should therefore not be considered limiting the scope of the present disclosure and may allow other equally valid embodiments.

It is a front perspective view of a waveguide combiner according to one embodiment. FIG. 5 is a flow chart of a method for forming a waveguide combiner according to one embodiment. FIG. 5 is a flow chart of a method for forming a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment. FIG. 5 is a schematic cross-sectional view of a portion of a waveguide combiner according to one embodiment.

For ease of understanding, the same reference numbers were used to indicate the same elements common to the figures, where possible. It is assumed that the elements and features of one embodiment can be beneficially incorporated into other embodiments without further description.

The embodiments described herein relate to a method of making a waveguide combiner having a grid having a front angle of less than about 45 ° and a back angle of less than about 45 °. This method involves imprinting a stamp on a nanoimprint resist placed on a substrate. Nanoimprint resists are exposed to the curing process. The stamp is released from the nanoimprint resist at an release angle θ using the release method. The nanoimprint resist is exposed to an annealing process to form a waveguide structure containing a plurality of lattices having a front angle α and a back angle β of less than about 45 ° with respect to a second plane of the substrate.

FIG. 1 is a front perspective view of the waveguide combiner 100. It should be understood that the waveguide combiner 100, which will be described later, is an exemplary waveguide combiner. The waveguide combiner 100 includes an input coupling region 102 defined by a plurality of grids 108, an intermediate region 104 defined by the plurality of grids 110, and an output coupling region 106 defined by the plurality of grids 112. The input coupling region 102 receives an incident beam of intense light (virtual image) from the microdisplay. Each grid of the plurality of grids 108 divides the incident beam into a plurality of modes, and each beam has a mode. The 0th order mode (T0) beam is refracted back or lost at the waveguide combiner 100, and the positive primary mode (T1) beam is coupled to the intermediate region 104 through the waveguide combiner 100 and is negative. The primary mode (T-1) beam of No. 1 propagates in the waveguide combiner 100 in the direction opposite to the T1 beam. Ideally, the incident beam is split into a T1 beam that has all the intensities of the incident beam in order to direct the virtual image towards the intermediate region 104. One technique for splitting the incident beam into T1 beams that have all the intensities of the incident beam is to optimize the tilt angle of each grid of multiple grids 108 in order to suppress the T-1 and T0 beams. be. The T1 beam undergoes total internal reflection (TIR) through the waveguide combiner 100 until it contacts a plurality of grids 110 in the intermediate region 104. A portion of the input coupling region 102 may have a grid 108 having a tilt angle of less than about 45 ° with respect to the surface of the waveguide combiner to suppress the T-1 and T0 beams.

The T1 beam contacts one grid of the plurality of grids 110. The T1 beam is a T0 beam that is refracted back or lost by the waveguide combiner 100, a T1 beam that undergoes TIR in the intermediate region 104 until the T1 beam contacts another grid of multiple grids 110, and a waveguide. It is divided into T-1 beams that are coupled to the output coupling region 106 through the combiner 100. The T1 beam that has undergone TIR in the intermediate region 104 has a depletion of the intensity of the T1 beam coupled to the intermediate region 104 via the waveguide combiner 100, or the remaining T1 beam propagating in the intermediate region 104 is in the intermediate region. It continues to contact several grids of the plurality of grids 110 until it reaches the end of 104. The plurality of grids 110 control the intensity of the T-1 beam coupled to the output coupling region 106 to modulate the field of view of the virtual image generated from the microdisplay from the user's point of view, allowing the user to see the virtual image. In order to increase the viewing angle, it must be tuned to control the T1 beam coupled to the intermediate region 104 through the waveguide combiner 100. One method of controlling the T1 beam coupled to the intermediate region 104 via the waveguide combiner 100 is to control the intensity of the T-1 beam coupled to the output coupling region 106 of a plurality of grids 110. It is to optimize the tilt angle of each grid. Part of the intermediate region 104 may have a grid 110 with an angle of inclination with respect to the surface of the waveguide combiner less than about 45 ° to control the intensity of the T-1 beam coupled to the output coupling region 106. ..

The T-1 beam coupled to the output coupling region 106 through the waveguide combiner 100 undergoes a TIR within the waveguide combiner 100 until the T-1 beam contacts one of the grids 112. In this case, the T-1 beam is refracted back or lost in the waveguide combiner 100 in the output coupling region 106 until the T0 beam, the T1 beam, contacts another grid of the plurality of grids 112. It is divided into a T1 beam that receives TIR and a T-1 beam that is coupled from the waveguide combiner 100. The T1 beam that receives the TIR in the output coupling region 106 is either depleted in intensity of the T-1 beam coupled to the output coupling region 106 through the waveguide combiner 100, or the remaining T1 beam propagating through the output coupling region 106. Continues to contact several grids of the plurality of grids 112 until either reaches the end of the output coupling region 106. The plurality of lattices 112 control the intensity of the T-1 beam connected from the waveguide combiner 100 to further modulate the field of view of the virtual image generated from the microdisplay from the user's point of view so that the user sees the virtual image. It must be tuned to control the T-1 beam coupled to the output coupling region 106 through the waveguide combiner 100 in order to further increase the resulting viewing angle. One technique for controlling the T-1 beam coupled to the output coupling region 106 through the waveguide combiner 100 is to optimize the tilt angle of each grid of the plurality of grids 112 to further modulate the field of view and increase the viewing angle. To let. A portion of the intermediate region 104 may have a grid 110 with an angle of inclination less than about 45 ° with respect to the surface of the waveguide combiner, which further modulates the field of view and increases the viewing angle.

One existing method of manufacturing waveguide combiners utilizes nanoimprint lithography. FIG. 2 is a flow diagram of a method 200 for forming a waveguide structure of a waveguide combiner such as the waveguide combiner 100. In step 201, the nanoimprint resist is a liquid material injection casting process, a spin-on coating process, a liquid spray coating process, a dry powder coating process, a screen printing process, a doctor braiding process, a physical vapor deposition (PVD) process, a chemical vapor deposition (PVD) process. It is deposited on the surface of a portion of the substrate using a deposition (CVD) process, a fluid CVD (FCVD) process, or an atomic layer deposition (ALD) process. Nanoimprint resists include at least one of spin-on glass (SOG), fluid SOG, organic, inorganic, and hybrid (organic and inorganic) nanoimprintable materials, which are silicon oxide (SiOC), dioxide. Titanium (TiO ₂ ), Silicon Dioxide (SiO ₂ ), Vanadium Oxide (IV) (VO _x ), Aluminum Oxide (Al ₂ O ₃ ), Indium Tin Oxide (ITO), Zinc Oxide (ZnO), Tantalum Pentoxide (Ta) _It may contain at least one of 2 O ₅ ), silicon nitride (Si ₃ N ₄ ), titanium nitride (TiN), and zinc oxide (ZrO _{2) -containing materials.} The material of the nanoimprint resist is partially selected based on the tilt angle of the resulting waveguide structure lattice formed from Method 200 and the index of refraction of the substrate to control the input and output coupling of light. , Facilitates light propagation through the waveguide combiner 100.

In step 202, the nanoimprint resist placed on a portion of the substrate is imprinted by stamping. In one embodiment, the nanoimprint resist is heated before the stamp is imprinted. The waveguide pattern includes a lattice pattern having a plurality of reciprocal lattices. Each of the plurality of reciprocal lattices has a reciprocal front angle with respect to the first plane on the back surface of the stamp and a reciprocal back angle with respect to the first plane on the back surface of the stamp. The stamp may be molded from a master and made from a translucent material such as fused silica or polydimethylsiloxane (PDMS) material, or a transparent material such as glass or plastic material, and may be made from infrared (IR) radiation or ultraviolet light. The nanoimprint resist can be cured by exposure to electromagnetic radiation such as (UV) radiation. In one embodiment, the stamp includes a rigid backing sheet, such as a sheet of glass, to add mechanical strength to the stamp. In step 203, the nanoimprint resist on the surface of the substrate is cured to stabilize the nanoimprint resist. In step 204, the stamp is released. The resulting waveguide structure includes a plurality of lattices corresponding to a plurality of reciprocal lattices, and thus each lattice of the plurality of lattices is also known as a gradient angle or an inclination angle with respect to a second plane of the surface of the substrate. It has a front angle and a back angle, also known as a gradient angle or tilt angle with respect to a second plane of the surface. In one embodiment, some waveguide structures on the substrate correspond to input coupling regions 102, intermediate regions 104, and / or output coupling regions 106 of the waveguide combiner 100.

A waveguide structure containing a grid with a front angle of less than about 45 °, a back angle of less than about 45 °, and adjusted dimensions such as grid height, residual layer height, grid top width, and grid bottom width. Manufacture can be difficult with stamps containing reciprocal lattices with opposite front and back angles of less than about 45 °. A stamp containing a reciprocal lattice with a reciprocal front angle of less than about 45 °, a reciprocal back angle of less than about 45 °, and a high aspect ratio (reciprocal lattice height to reciprocal lattice width) is imprinted on the nanoimprint resist and resisted. The resulting waveguide structure may have overlapping lattices, making it impossible to remove stamps without lattice damage. For example, the aspect ratio can be from about 2: 1 to about 3: 1.

FIG. 3 is a flow chart of the method 300 for forming the waveguide structure 400 shown in FIGS. 4A-4F. In one embodiment, the waveguide structure 400 corresponds to an input coupling region 102, an intermediate region 104, and / or an output coupling region 106 of the waveguide combiner 100. In step 301, as shown in FIG. 4A, the nanoimprint resist 408 is used in a liquid material injection casting process, spin-on coating process, liquid spray coating process, dry powder coating process, screen printing process, doctor braiding process, PVD process, CVD process. , FCVD process, or ALD process is used to deposit on the surface 406 of a portion 402 of the substrate 404. Nanoimprint resists include SOG, fluidity, materials containing SiOC, TiO ₂ , SiO ₂ , VO _x , Al ₂ O ₃ , ITO, ZnO, Ta ₂ O ₅ , Si ₃ N ₄ , TiN, and zirconium dioxide ZrO _2. It may include at least one of SOG, organic, inorganic, and / or hybrid organic and inorganic nanoimprintable materials. The material for the nanoimprint resist is selected based on the anterior, posterior, and adjusted dimensions of the plurality of lattices of the waveguide structure 400 formed by method 300. In one embodiment, the nanoimprint resist comprises a proportion of sol-gel solution that may contain _{SiO 2} , silicon carbide (SiOC), ZrO ₂ , or TiO _{2 containing material.}

In step 302, the stamp 410 is imprinted on the nanoimprint resist 408. In one embodiment, the nanoimprint resist 408 is heated to a preheating temperature before the stamp 410 is imprinted. The preheating temperature is a temperature that promotes evaporation of the solvent in the nanoimprint resist 408. In one embodiment, the preheating temperature is from about 50 ° C to about 60 ° C. The stamp 410 has a plurality of reciprocal lattices 414. The stamp 410 may be molded from a master and made from a translucent material such as fused silica or polydimethylsiloxane (PDMS) material, or a transparent material such as glass or plastic material, and may emit infrared (IR) radiation or The nanoimprint resist can be cured by exposure to electromagnetic radiation such as ultraviolet (UV) radiation. In one embodiment, the stamp 410 may be coated with a single layer of anti-adhesive surface treatment coating such as a fluorinated coating, thus the stamp 410 may be peeled off by a machine tool or by hand at an open angle θ'. It can be removed mechanically. In another embodiment, the stamp 410 includes a rigid backing sheet, such as a sheet of glass, to add mechanical strength to the stamp 410 and release the stamp 410 at a release angle θ ″.

As shown in FIG. 4B, the stamp 410 has a plurality of reciprocal lattices having an inverted front angle α and an inverted back angle β with respect to the first plane 416 of the back surface 415 of the stamp 410. The reverse front angle α and the reverse back angle β are about 45 ° or more. Explain the shrinkage of the nanoimprint resist 408 from the curing process to the release state and from the annealing process to the annealing state, and as a result of the release method and release angle of the stamp 410, the front and back angles of the nanoimprint resist 408 in the open state, and To illustrate the modification of the second dimension, the plurality of reciprocal lattices 414 have a first dimension of height h, pitch p, lattice top width w _t , and lattice bottom width w _b . In one embodiment, the nanoimprint resist 408 can shrink by 20%. By shrinking the nanoimprint resist 408, the refractive index of the nanoimprint resist 408 can be increased. The master has a pattern such that the stamp 410 formed from the master has a plurality of reciprocal lattices 414 having a height h, a pitch p, a grid top width w _t , and a grid bottom width w _b. The height h is the height from the top of the reciprocal lattice 418 to the bottom of the reciprocal lattice 420. The lattice upper width w _t is the width of the reciprocal lattice upper 418, and the lattice lower width w _b is the width of the reciprocal lattice bottom 420. The pitch p is the distance between the first edges 422 of the reciprocal lattice upper part 418.

In step 303, the nanoimprint resist 408 is exposed to the curing process. Prior to the curing process, the nanoimprint resist 408 is in a green state, also known as a gel state, which means that an organic binder is present in the nanoimprint resist 408. The curing process involves exposing the nanoimprint resist 408 to electromagnetic radiation, such as infrared (IR) or ultraviolet (UV) radiation, until the nanoimprint resist reaches a stripped state. Since the nanoimprint resist 408 can still be in the green state in the open state, the nanoimprint resist 408 has dimensions of the front angle α'and the back angle β'and the nanoimprint resist 408 as a result of the release method and the release angle of the stamp 410. It is malleable so that it can be modified. However, in the open state, the amount of organic binder is decreasing. The nanoimprint resist 408 is in the released state when the nanoimprint resist 408 reaches the curing temperature corresponding to the released state. In one embodiment, the curing temperature is from about 30 ° C to about 80 ° C.

In step 304, the stamp 410 is released from the nanoimprint resist 408 in the released state. As shown in FIG. 4C, the stamp 410 is peeled from the nanoimprint resist 408 in the open state with respect to the second plane 438 of the surface 406 of the substrate 404 at an release angle θ'. In one embodiment, the stamp 410 is mechanically peeled off by a machine tool at an open angle θ'. In another embodiment, the stamp 410 is manually peeled off at a release angle θ'. In other embodiments, the release angle θ'is from about 0 ° to about 180 °. In one embodiment, the stamp 410 is stripped from the first end 424 and the second end 426, or from the second end 426 to the first end 424. For example, peeling from the first end 424 to the second end 426 results in lower front and back angles, and peeling from the second end 426 to the first end 424 results in higher front and back angles. Can bring horns. In another embodiment, the stamp is stripped along the grid direction 442. Peeling along the grid direction 442 reduces pattern collapse. After the stamp 410 peeled off at the release angle θ', the front angle, back angle, and dimensions of the nanoimprint resist 408 are modified. The open nanoimprint resist 408 has a plurality of transition grids 412 having a front angle α'and a back angle β'. The plurality of transition grids 412 have a second dimension having a transition height h', a transition pitch p', a transition grid top width w _t ', a transition grid bottom width w _b ', and a transition residual layer height r'. .. The front angle α'and the back angle β'are for the second plane 438 of the surface 406 of the substrate 404. The transition residual layer height r'is the height from the surface 406 of the substrate 404 to the upper 430 of the residual layer 428. The transition height h'is the height from the top of the grid 432 to the bottom of the grid 434. Transition lattice upper width w _{t 'is} the width of the grating top 432, the transition lattice bottom width w _b' is the width of the grating bottom 434. The transition pitch p'is the distance between the first edges 436 of the upper grid 432. In one embodiment, the front angle α'and the back angle β, the transition height h', the transition grid top width w _t ', the transition grid bottom width w _b ', and the transition residual layer height r'are stamps 410. Adjusted from curing process and release.

As shown in FIG. 4D, the stamp 410 is lifted from the nanoimprint resist 408 from the nanoimprint resist 408 at a release angle θ'' with respect to the second plane 438 of the surface 406 of the substrate 404 in the open state. In one embodiment, the stamp 410 is mechanically lifted by a machine tool at an open angle θ''. In another embodiment, the stamp 410 is lifted by hand at a release angle θ''. In some embodiments, the release angle θ'' is from about 0 ° to about 180 °. An open angle θ'' with respect to a second plane 438 of less than about 90 ° will result in a denser grid. After the stamp 410 is lifted at the release angle θ'', the front angle, back angle, and dimensions of the nanoimprint resist 408 are modified. The nanoimprint resist 408 in the open state has a front angle α'' and a back angle β'', a transition height h'', a transition pitch p'', a transition lattice top width w _t '', and a transition lattice bottom width w _b '. It has a plurality of transition lattices 412 having'and a transition residual layer height r''. In one embodiment, when the normal force from the peel can be controlled to affect the plurality of transition grids 412, the front, back, and second dimensions of the transition grid 412 from the peel, as well as lifting. The front angle, back angle, and second dimension of the transition grid 412 from are different. In one embodiment, the front angle α'' and the back angle β'', the transition height h'', the transition grid top width w _t '', the transition grid bottom width w _b '', and the transition residual layer height r. '' Is adjusted from the curing process and release of stamp 410.

In step 305, the waveguide structure 400 is formed by exposing the nanoimprint resist 408 to an annealing process. The annealing process involves exposing the nanoimprint resist 408 to electromagnetic radiation, such as infrared (IR) or ultraviolet (UV) radiation, until the nanoimprint resist reaches an annealing state. In the annealed state, the nanoimprint resist 408 is rigid and therefore not flexible and not in the green state. When the nanoimprint resist 408 reaches the annealing temperature corresponding to the annealing state, it goes into the annealing state. In one embodiment, the annealing temperature is from about 150 ° C to about 250 ° C. The annealing process reduces the volume of nanoimprint resist 408. Therefore, as shown in FIG. 4E, the waveguide structure 400 formed by peeling the stamp 410 at the release angle θ'has a plurality of lattices 440 having ^{a front angle α 1} and a back angle β ^1. The plurality of grids 440 have a third dimension having ^{a height h 1} , a pitch p ¹ , a grid top width w _t ¹ , a grid bottom width w _b ¹ , and a residual layer height r ^1. In one embodiment, the front angle α ¹ and the back angle β ¹ , the height h ¹ , the grid top width w _t ¹ , the grid bottom width w _b ¹ , and the residual layer height r ¹ are adjusted from the annealing process. .. As shown in FIG. 4F, the waveguide structure 400 formed by lifting the stamp 410 at an open angle θ'' has a plurality of grids 440 having ^{a front angle α 2} and a back angle β ^2. The plurality of grids 440 have a third dimension having ^{a height h 2} , a pitch p ² , a grid top width w _t ² , a grid bottom width w _b ² , and a residual layer height r ^2. In one embodiment, the front angle α ² and the back angle β ² , the height h ² , the grid top width w _t ² , the grid bottom width w _b ² , and the residual layer height r ² are adjusted from the annealing process. .. In another embodiment, the anterior, posterior, and dimensions of the plurality of grids 440 from peeling and the anterior, posterior, and dimensions of the transition grids 412 from lifting are different. The front angle α ¹ , the back angle β ¹ , the front angle α ² , and the back angle β ² are less than about 45 °. In another embodiment, the front angle α ¹ and the back angle β ¹ are from about 32 ° to about 37 °. In yet another embodiment, the front angle α ² and the back angle β ² are less than 37 °, for example from about 32 ° to about 37 °.

In another embodiment, after step 304 and before step 305, backfill material 401 is deposited between each transition grid of the plurality of transition grids 412, as shown in FIGS. 4G and 4H. Material 401 has a second index of refraction that is substantially commensurate with or greater than the first index of refraction of the nanoimprint resist 408. The backfill material 401 is said to be at least one of a material containing _{SiOC, TiO 2} , SiO ₂ , VO _x , Al ₂ O ₃ , ITO, ZnO, Ta ₂ O ₅ , Si ₃ N ₄ , TiN, and ZrO _2. , SOG, fluid SOG, organic nanoimprintable materials, inorganic nanoimprintable materials, and at least one of hybrid (organic and inorganic) nanoimprintable materials. The backfill material 401 uses a liquid material injection casting process, spin-on coating process, liquid spray coating process, dry powder coating process, screen printing process, doctor braiding process, PVD process, CVD process, FCVD process, or ALD process. Therefore, it can be deposited between each transition lattice of the plurality of transition lattices 412. As shown in FIGS. 4I and 4J, the nanoimprint resist 408 is exposed to the annealing process along with the backfill material 401 for a substantially balanced first and second index of refraction. The backfill material 401 further stresses the plurality of transition grids 412 in order to reduce ^{the front angle α 1} and the back angle β ¹ of the plurality of grids 440 of the waveguide structure 400 formed by peeling the stamp 410. Add. The backfill material 401 further stresses the plurality of transition grids 412 in order to reduce ^{the front angle α 2} and the back angle β ² of the waveguide structure 400 formed by lifting the stamp 410.

Taken together, a method of making a waveguide combiner with a grid having a front angle of less than about 45 °, a back angle of less than about 45 °, and adjusted dimensions is described herein. The stamp has an inverted front angle α, an inverted back angle β, and multiple reciprocal lattices with dimensions, explaining the reduction in volume of the nanoimprint resist from the curing and annealing processes, and the front angle of the nanoimprint resist in the open state. And the modification of the back angle and the dimensions will be described. As a result of the stamp release method and release angle, the multiple grids of the waveguide combiner have a front angle of less than 45 °, a back angle of less than 45 °, and adjusted dimensions.

Although the above is intended for the embodiments of the present disclosure, other embodiments and further examples of the present disclosure may be devised without departing from the basic scope of the present disclosure, and the scope of the present disclosure. Is determined by the following claims.

Claims (15)

This is a method for manufacturing a waveguide structure.
Imprinting a stamp on a nanoimprint resist placed on the surface of a substrate.
A reverse front angle α of about 45 ° or more with respect to the first plane of the back surface of the stamp,
Imprinting a stamp comprising a reciprocal lattice β having an inverted back angle β of about 45 ° or more with respect to the first plane and a first dimension.
Exposing the nanoimprint resist to the curing process
Using the release method, the stamp is released from the nanoimprint resist at an release angle θ.
To form a waveguide structure, the nanoimprint resist is exposed to an annealing process, wherein the waveguide structure is:
Front angle α, less than about 45 ° with respect to the second plane of the surface of the substrate,
A method comprising exposing the nanoimprint resist to an annealing process, comprising a back angle β less than about 45 ° with respect to the second plane, and a plurality of grids having a third dimension. The method of claim 1, wherein the curing process comprises exposing the nanoimprint resist to electromagnetic radiation until the nanoimprint resist reaches an open state. The method of claim 2, wherein the stamp is coated with a single layer of anti-adhesive surface treatment coating so that it is removed by peeling at an opening angle θ'. The release method of peeling the stamp from the nanoimprint resist at the release angle θ'forms a plurality of transition lattices, and the plurality of transition lattices form a plurality of transition lattices.
Transition front angle α', with respect to the second plane of the surface of the substrate
The method of claim 3, which has a transition back angle β'with respect to the second plane and a second dimension. The method of claim 2, wherein the stamp comprises a rigid backing sheet for releasing the stamp at a release angle θ ″, in addition to adding mechanical strength to the stamp. The release method of lifting the stamp from the nanoimprint resist at the release angle θ'' forms a plurality of transition lattices, and the plurality of transition lattices form a plurality of transition lattices.
Transition front angle α'', with respect to the second plane of the surface of the substrate
The method of claim 5, which has a transition back angle β'' with respect to the second plane and a second dimension. The method according to claim 2, wherein the nanoimprint resist is in the released state when it reaches a curing temperature of about 30 ° C to about 80 ° C. The method of claim 1, wherein the nanoimprint resist comprises at least one of spin-on glass (SOG), fluid SOG, organic, inorganic, and hybrid (organic and inorganic) nanoimprintable materials. The nanoimprintable materials are silicon oxycarbonate (SiOC), titanium dioxide (TiO ₂ ), silicon dioxide (SiO ₂ ), vanadium oxide (IV) (VO _x ), aluminum oxide (Al ₂ O ₃ ), and indium tin oxide. At least one of (ITO), zinc oxide (ZnO), tantalum pentoxide (Ta ₂ O ₅ ), silicon nitride (Si ₃ N ₄ ), titanium nitride (TiN), and zirconium dioxide (ZrO ₂ ) -containing material. 8. The method of claim 8. The method of claim 9, wherein the nanoimprint resist comprises a sol-gel solution. The method of claim 1, wherein the annealing process comprises exposing the nanoimprint resist to electromagnetic radiation until the nanoimprint resist reaches an annealing state. The method according to claim 11, wherein when the nanoimprint resist reaches an annealing temperature of about 150 ° C. to about 250 ° C., it becomes an annealed state. The nanoimprint resist is a liquid material injection casting process, spin-on coating process, liquid spray coating process, dry powder coating process, screen printing process, doctor braiding process, physical vapor deposition (PVD) process, chemical vapor deposition (CVD). The method of claim 1, wherein a process, a fluid CVD (FCVD) process, or an atomic layer deposition (ALD) process is used to deposit on the surface of the substrate. This is a method for manufacturing a waveguide structure.
Imprinting a stamp on a nanoimprint resist placed on the surface of a substrate.
A reverse front angle α of about 45 ° or more with respect to the first plane of the back surface of the stamp,
Imprinting a stamp comprising a reciprocal lattice β having an inverted back angle β of about 45 ° or more with respect to the first plane and a first dimension.
Exposing the nanoimprint resist to the curing process so that the nanoimprint resist is in an open state,
A release method is used in which the stamp is released from the nanoimprint resist in the released state, and the stamp is peeled off from the nanoimprint resist in the released state at an release angle θ'to form a plurality of transition lattices. Including that, the plurality of transition lattices
Transition front angle α', with respect to the second plane of the surface of the substrate
To release the stamp, which has a transition back angle β'with respect to the second plane, and a second dimension.
The nanoimprint resist is exposed to an annealing process that involves forming a waveguide structure from the nanoimprint resist in an annealed state.
^{Front angle α 1} , less than about 45 ° with respect to the second plane of the surface of the substrate,
^{A method comprising exposing the nanoimprint resist comprising a back angle β 1} less than about 45 ° to the second plane and a plurality of grids having a third dimension. This is a method for manufacturing a waveguide structure.
Imprinting a stamp on a nanoimprint resist placed on the surface of a substrate.
A reverse front angle α of about 45 ° or more with respect to the first plane of the back surface of the stamp,
Imprinting a stamp comprising a reciprocal lattice β having an inverted back angle β of about 45 ° or more with respect to the first plane and a first dimension.
Exposing the nanoimprint resist to the curing process so that the nanoimprint resist is in an open state,
A release method is used in which the stamp is released from the nanoimprint resist in the released state, and the stamp is lifted from the nanoimprint resist in the released state at an release angle θ'' to form a plurality of transition lattices. Including that, the plurality of transition lattices
Transition front angle α'', with respect to the second plane of the surface of the substrate
To release the stamp, which has a transition back angle β'' with respect to the second plane, and a second dimension.
The nanoimprint resist is exposed to an annealing process that involves forming a waveguide structure from the nanoimprint resist in an annealed state.
^{Front angle α 2} , less than about 45 ° with respect to the second plane of the surface of the substrate,
^{A method comprising exposing the nanoimprint resist comprising a back angle β 2} less than about 45 ° to the second plane and a plurality of grids having a third dimension.

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